Preexisting nuclear architecture defines the intranuclear location of herpesvirus DNA replication structures

Abstract

Herpes simplex virus DNA replication proteins localize in characteristic patterns corresponding to viral DNA replication structures in the infected cell nucleus. The intranuclear spatial organization of the HSV DNA replication structures and the factors regulating their nuclear location remain to be defined. We have used the HSV ICP8 DNA-binding protein and bromodeoxyuridine labeling as markers for sites of herpesviral DNA synthesis to examine the spatial organization of these structures within the cell nucleus. Confocal microscopy and three-dimensional computer graphics reconstruction of optical series through infected cells indicated that viral DNA replication structures extend through the interior of the cell nucleus and appear to be spatially separate from the nuclear lamina. Examination of viral DNA replication structures in infected, binucleate cells showed similar or virtually identical patterns of DNA replication structures oriented along a twofold axis of symmetry between many of the sister nuclei. These results demonstrate that HSV DNA replication structures are organized in the interior of the nucleus and that their location is defined by preexisting host cell nuclear architecture, probably the internal nuclear matrix.

Mitotic Transcription Repression in Vivo in the Absence of Nucleosomal Chromatin Condensation

“…1 b shows four frames from a 3-D animated movie of an interphase cell infected with HSV-1 for 6 h. (Video 1 is available at http://www.jcb.org/cgi/content/full/150/1/13/DC1) The interphase cell contained two large viral replication compartments that occupied most of the cell nucleus. Viral and cellular DNA appeared to occupy discrete intranuclear regions, with cellular DNA concentrated at the nuclear periphery, as seen previously (de Bruyn Kops and Knipe 1994; Besse et al 1995). Fig.…”

Targeting of the gene product encoded by ORF UL56 of human cytomegalovirus into viral replication centers

“…were co-immunoprecipitated with pabUL56 (1, 2), mAb RG#1202 (3,4) or anti-gB mAb 27-156 (5,6) and subjected to SDS^PAGE prior to transfer onto nitrocellulose and autoradiographic analysis. (C) The identical immunoprecipitates of mock-infected (1,3,5) or HCMV-infected (2,4,6) HFF together with extracts of mock- (7) and HCMV-infected cells (8) were subjected to immunoblot analysis using antibody RG#1202. The arrows indicate the position of pUL56, pUL44 and gB, the molecular weight markers (MW) are indicated on the left.…”

Replication Compartments of DNA Viruses in the Nucleus: Location, Location, Location

“…Firstly, incoming genomes must avoid cellular intrinsic antiviral defenses and homeostatic regulatory pathways such as elements of the DNA damage response (DDR) that respond to the presence of foreign DNA and act to suppress viral gene expression [3][4][5][6][7][8][9][10]. Secondly, VRCs typically form at specific sites within the nucleus, suggesting that viral genomes need to be targeted to these sites in order to initiate VRC formation [6,11,12]. Furthermore, it has been hypothesized that the formation and growth of VRCs may require manipulation of the nuclear environment and the re-organization of host chromatin to overcome the spatial restraints of the nucleus [11][12][13][14][15].…”

“…Secondly, VRCs typically form at specific sites within the nucleus, suggesting that viral genomes need to be targeted to these sites in order to initiate VRC formation [6,11,12]. Furthermore, it has been hypothesized that the formation and growth of VRCs may require manipulation of the nuclear environment and the re-organization of host chromatin to overcome the spatial restraints of the nucleus [11][12][13][14][15]. In this section, we review key features of VRC initiation and highlight some major challenges to VRC formation.…”